'87 April was allegedly based on Fujiko Mine. I don't know anybody who had heard of Lupin III in the states at that time.
Plus in 2007, there was this thing called "the internet", so I'm sure there were more than just a few people who knew what Devilman was. I mean, it likely didn't have a substantial fanbase, but I mean, I'd heard of it by 2007.
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